When previously eviscerated poultry carcasses are to be cut into parts, it is desirable that the parts be accurately separated from one another so that bone chips or fragments are not formed during the separating process and are not found in the separated parts. Further, it is desirable that the separating functions be performed in a rapidly operating automated system which accurately separates the parts from one another.
In recent years, more extensive use has been made of the overhead conveyor system in poultry processing plants, whereby the birds are suspended from an overhead conveyor system in an inverted attitude, with the legs of the bird supported in shackles that are carried by the conveyor system. The shackles move the birds through one or more processing stages, such as a vent cutter, a bird opener, an eviscerator, a neck breaker, a lung puller, and a crop remover. Further, the birds can be moved through various parts separating devices so that the carcasses are subdivided into, for example, separated breasts, backs, wings, legs and thighs.
It has been known in the art to cut the legs from the back portion with rotary blades as the poultry is moved along the overhead conveyor. As a consequence of this manner of cutting, part of the peritoneum and some fat may be left on the legs, whereas the so-called oysters are often partially or entirely left on the back portion. For quality's sake, the opposite result should be achieved.